Richard Shiffrin is the Luther Dana Waterman Professor of cognitive science for the Department of Psychological and Brain Sciences at Indiana University, Bloomington. Shiffrin has contributed a number of theories of attention and memory to the field of psychology. He co-authored the Atkinsin-Shiffrin model of memory in 1968 with Richard Atkinson[1], who was his academic adviser at the time. In 1977, he published a theory of attention with Walter Schneider [2]. With Jeroen G.W. Raaijmakers in 1980, Shiffrin published the Search of Associative Memory (SAM) model[3], which has served as the standard model of recall for cognitive psychologists well into the 2000s[4]. He extended the SAM model with the Retrieving Effectively From Memory (REM) model in 1997 with Mark Steyvers[5].